Metabolic management following bariatric surgery.

Bariatric surgery is an effective treatment option for obesity. Commonly utilized procedures are either restrictive, malabsorptive, or both. Substantial weight loss can be achieved. Postoperatively, patients experience nutritional, metabolic, and hormonal changes that have important clinical implications. The postoperative diet should be advanced carefully, according to protocol. Micronutrient deficiencies such as vitamin C, vitamin A, and zinc deficiencies are common, especially following malabsorptive procedures. Bone metabolism is greatly affected, in part due to vitamin D deficiency, decreased calcium absorption, and secondary hyperparathyroidism. Diabetes improves acutely in malabsorptive procedures and in sequence with weight loss in restrictive procedures. Polycystic ovarian syndrome improves in nearly all women with this condition who undergo bariatric surgery. Testosterone levels in men also improve after surgery. Consideration of these nutritional, metabolic, and hormonal changes allows for optimal medical management following bariatric surgery.